Sam Cannon demonstrates in support of striking fast-food workers at a McDonald's restaurant on East Riverside Drive in Austin, Texas on Tuesday. About 50 fast-food workers and supporters chanted as they marched past several restaurants in the area.

Workers in nearly 20 major airports, Uber drivers, and fast food restaurant employees in as many as 340 US cities are expected to strike on Tuesday in a call for higher minimum wages.

Employees from baggage handlers to fast-food restaurant cashiers plan to skip their shifts and join picket lines on the "Day of Disruption," with the most visible demonstration possibly occurring in the nation’s second busiest airport, Chicago O'Hare International Airport, where 500 workers submitted strike notices to their employers.

"We work so hard and we hardly even get breaks," Kisha Rivera, a cabin cleaner at the O’Hare airport, told CNN. She said some of her coworkers sleep in the airports because they can't afford apartments. "When we go from plane to plane, we can't even go to the bathroom."

Organized by advocacy group Fight for $15, the protest is in its fourth anniversary in fighting for a $15 minimum wage nationwide through protests and demonstrations, scoring past successes in places such as New York and California. This year, the organizers say they have planned their "most disruptive protests yet," to send a message to the newly elected government, hoping to build on the momentum after four states voted to raise their minimum wages in the November elections.

The protests are intended to "let President-elect Donald Trump, members of Congress, governors, state legislators and other elected leaders know that the 64 million Americans paid less than $15 an hour are not backing off their demand for $15 per hour and union rights," the Service Employees International Union (SEIU), who voted to back the strikes, said in a statement, according to the Pittsburgh Post-Gazette.

By early Tuesday morning, nearly a hundred workers from McDonald’s walked out and staged protests in Pittsburgh, the Post-Gazette reports, with similar scenes occurring in multiple cities including Milwaukee and Phoenix. The Chicago O’Hare airport workers began their strike 10 p.m. Monday and will join other protestors at a 12 p.m. rally on Tuesday.

The current federal minimum wage is at $7.25 per hour. Three states – Arizona, Colorado, and Maine – voted in November to increase it to $12 by 2020, while Washington state voted to increase it to $13.50 by then. Chicago’s legal minimum wage is at $10.50 per hour. In April, California Gov. Jerry Brown signed a bill to raise the minimum wage for hourly workers to $15 by 2023, just as New York Gov. Andrew Cuomo signed a two-tier minimum wage bill, raising most wages in New York City to $15 by 2018, and more slowly outside of the city. Laws to increase minimum wages are already in place in several individual cities, including Los Angeles and Seattle.

Most workers earning minimum wages at or below the federal level, according to the Bureau of Labor Statistics, are in the leisure and hospitality industry, especially in restaurants and other food services.Fight for $15 has often in the past galvanized fast-food workers to strike for better treatment, although over the years, it has expanded to workers in other service industries.

Uber drivers are a new addition to the strikes. In San Francisco, Uber’s hometown, drivers are planning to march at the airport, according to CNN, while Uber drivers in other cities will march with low-wage workers from other sectors.

"Everyone says the gig economy is the future of work, but if we want to make that future a bright one, we need to join together like fast-food workers have in the Fight for $15 and demand an economy that works for all," Justin Berisie, an Uber driver base in Denver, said in a statement, CNN reported.

In Chicago, the airport workers' woes are not new. They have already submitted complaints about poor working conditions, wage theft, and unsafe working conditions to the Department of Aviation, state Department of Labor, and the federal Occupational Health and Safety Administration, according to the Chicago Sun-Times.

"We do expect there will be delays," Izabela Miltko, a spokeswoman for SEIU Local 1 told the paper, "But these workers' goal is not to shut down the airport."